1 files changed, 52 insertions, 0 deletions
diff --git a/src/main/java/org/onap/music/util/TimeMeasure.java b/src/main/java/org/onap/music/util/TimeMeasure.java
new file mode 100644
index 00000000..cbb04ff6
--- /dev/null
+++ b/src/main/java/org/onap/music/util/TimeMeasure.java
@@ -0,0 +1,52 @@
+package org.onap.music.util;
+
+import org.apache.commons.lang3.tuple.Pair;
+
+import java.text.DecimalFormat;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Map;
+import java.util.concurrent.ThreadLocalRandom;
+
+public interface TimeMeasure {
+    void enter(String context);
+
+    void exit();
+
+    /*
+        Return a map of measure contexts to a list of 101 percentiles [0,100]
+     */
+    Map<String, ArrayList<Double>> percentiles();
+
+    /*
+        Returns a map of measure contexts to <mean, sme>
+     */
+    Map<String, Pair<Double, Double>> stats();
+}
+
+class TimeMeasureExample
+{
+    public static void main(String[] args) {
+        TimeMeasure tm = new SamplerHistogramTimeMeasure();
+        double x = 0;
+
+        tm.enter("A");
+        for (int i = 0; i < 100000; i++) {
+            tm.enter("B");
+            tm.enter("C");
+            x += ThreadLocalRandom.current().nextDouble(100);
+            tm.exit();
+            tm.exit();
+        }
+        tm.enter("C");
+        tm.exit();
+        tm.exit();
+
+        System.out.println(x);
+        Map<String, ArrayList<Double>> e = tm.percentiles();
+        Map<String, Pair<Double, Double>> m = tm.stats();
+        DecimalFormat df = new DecimalFormat("000.000000");
+        e.forEach((k,v) -> System.out.println("" + k + "\t\t: " + Arrays.toString(v.stream().map(w -> "" + df.format(w)).toArray())));
+        m.forEach((k,v) -> System.out.println("" + k + "\t\t: " + df.format(v.getLeft()) + " (" + df.format(v.getRight()) + ")"));
+    }
+}